Conventionally, there has been known a wheel speed detecting device that detects a rotating state of a pulsar ring mounted to a wheel by a magnetic sensor mounted to a vehicle body side. In such a wheel speed detecting device, positioning accuracy of the pulsar ring affects accuracy of the sensor output.
Patent Literature 1 discloses the following wheel speed detecting device. A pulsar ring includes pulsar holes as detected portions near the outer periphery. The pulsar ring forms a cylindrical-shaped convex-side spigot portion at a center in a radial direction by drawing. The convex-side spigot portion is inserted into a concave-side spigot portion formed on a wheel hub of a wheel to align a center position of the pulsar ring.